Atmospheric Transport of Artificial Radioactivity

Journal Article · Fri Nov 25 04:00:00 EST 1960 · Science

DOI:https://doi.org/10.1126/science.132.3439.1523· OSTI ID:4109656

Martell, E. A.; Drevinsky, P. J.

The principal shortcoming common to previous attempts to interpret the atmospheric behavior of fall-out is the failure to distinguish the iufluence of latitude, altitude, and time of injection on the storage time and fall-out pattern for stratospheric sources. On the basis of evidence provided by fission- product concentration ratios in precipitation, Mantell pointed out that the short- lived radioisotopes in world-wide fall-out were principally of stratospheric origin and that stratospheric storage times decrease markedly with latitude and increase with altitude. Use was made of 12.8-d Ba¹⁴⁰, 53-d Sr⁸⁹, 28- y Sr⁹⁰, and 74-d W¹⁸⁵ concentrations in individual precipitation samples in interpreting some major features of transpont and deposition patterns for stratospheric fall-out. The usefulness of fission-product ratio data for estimating the relative con tribution of various nuclear-test sources to total fall-out has been questioned on the basis of possibly serious physical and chemical fractionation effects and uncertainties in fission-product production- yield ratios. The chemical similarity of barium and strontium limits chemical fractionation effects on Ba¹⁴⁰/Sr⁹⁰ ratio data; Sr⁸⁹/Sr< s9>s⁰ ratio data obviously are unaffected by chemical factors. Uncertainties due to the use of production-ratio values, or due to the assumption that there are no fractionation effects, do not seriously affect the usefulness of isotope- ratio data for distinguishing major differences in atmospheric behavior of nuclear-cloud sources of different altitude and latitude for well-spaced nuclear tests. The U. S. Hardtack nuclearteat series provided a useful tracer in W¹⁸⁵ for studying the behavior of fall-out debris from equatorial tests. Data are given for Ba¹⁴⁰/Sr⁹⁰ and Sr⁸⁹/Sr⁹⁰ ratio s and for Sr⁹⁰ and W¹⁸⁵ concentrations in rainfall for various time periods.

• Research Organization: Geophysics Research Directorate, Bedford, Mass.
• Sponsoring Organization: USDOE
• NSA Number: NSA-15-006228
• OSTI ID: 4109656
• Journal Information: Science, Journal Name: Science Journal Issue: 3439 Vol. 132; ISSN 0036-8075
• Publisher: AAAS
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

07 ISOTOPE AND RADIATION SOURCES
ATMOSPHERE
BARIUM 140
CHEMICAL REACTIONS
CONFIGURATION
DISTRIBUTION
FALLOUT
FISSION PRODUCTS
HALF-LIFE
NUCLEAR EXPLOSIONS
PRECIPITATION
RADIOISOTOPES
RAIN
SEPARATION PROCESSES
STORAGE
STRATOSPHERE
STRONTIUM 89
STRONTIUM 90
TRACER TECHNIQUES
TRANSPORT
TUNGSTEN 185
VELOCITY